FLUX CLOSURE IN MAGNETIC FORCE MICROSCOPE TIPS

This work considers the effect of MFM tip magnetisation distribution o n force gradient images of Co/Pt perpendicular anisotropy multilayer m aterials. In particular it is shown that a pyramidal tip with a Co coa ting which is thought to contain closure domain structures produces su bstantially different images from single domain CoPt coated tips. Mode lling results are also presented which support the closure domain hypo thesis. It is concluded that the small effective volume of the closure tip produces valuable results in terms of resolution and image clarit y.